A minimal, nonlinear oscillator model is analyzed for the Madden–Julian oscillation (MJO) ‘‘skeleton’’ (i.e., its fundamental features on intraseasonal/planetary scales), which includes the following: (i) a slow eastward phase speed of roughly 5 m s, (ii) a peculiar dispersion relation with dv/dk ’ 0, and (iii) a horizontal quadrupole vortex structure. Originally proposed in recent work by the ...

Convectively coupled Kelvin waves (CCKWs) are atmospheric weather systems that propagate eastward along the equatorial wave guide with phase speeds between 11 and 14ms . They are an important constituent of the convective envelope of the Madden-Julian oscillation (MJO), for which ocean-atmosphere interactions play a vital role. Hence, ocean-atmosphere interactions within CCKWs may be important ...

A common practice in the design of forecast models for ENSO is to couple ocean general circulation models to simple atmospheric models. Therefore, by construction these models (known as hybrid ENSO models) do not resolve various kinds of atmospheric variability [e.g., the Madden–Julian oscillation (MJO) and westerly wind bursts] that are often regarded as “unwanted noise.” In this work the sens...

The influence of the Madden-Julian Oscillation (MJO) on surface air temperature over Iran is examined using daily data from meteorological stations 1979 to 2015. Composites anomalies are positive in MJO phases 1 and 8 negative 3–4 with broader region tendencies also 2 7, 5–6. This variability associated horizontal advection, whereby southerly (northward) winds act heat northerly (southward) coo...

1. Introduction A number of studies have shown that the Madden-Julian Oscillation (MJO) have a strong influence on the atmospheric circulation and precipitation patterns in the Recent studies also suggest that the MJO-related tropical forcing is linked to precipitation events along the west coast of the United State during the winter season (Mo and Higgins 1998; Higgins et al. 2000). Dynamical ...

The intraseasonal fluctuations of Indian summer monsoon rainfall (ISMR) are mainly controlled by northward propagating oscillation (MISO) and eastward Madden Julian (MJO). In the current study, we examine relationship between (active break spells) ISMR with phase propagation amplitude MISO MJO. We notice that active spells generally occur during phases 2–5 (MJO 3–6), 6–8 1). association active/...

The Madden-Julian oscillation (MJO) is the dominant mode of variability in the tropical atmosphere on intraseasonal timescales and planetary spatial scales. Despite the primary importance of the MJO and the decades of research progress since its original discovery, a generally accepted theory for its essential mechanisms has remained elusive. Here, we present a minimal dynamical model for the M...

[1] We investigate the modulation of aerosols by the Madden-Julian Oscillation (MJO) using multiple, global satellite aerosol products: aerosol index (AI) from the Total Ozone Mapping Spectrometer (TOMS) on Nimbus-7, and aerosol optical thickness (AOT) from the Moderate Resolution Imaging Spectroradiometer (MODIS) on Terra and Aqua and the Advanced Very High Resolution Radiometer (AVHRR) on NOA...

In Part I of this study it was shown that moving from a moisture-convergentto a relative-humidity-dependent organized entrainment rate in the formulation for deep convection was responsible for significant advances in the simulation of the Madden–Julian Oscillation (MJO) in the ECMWF model. However, the application of traditional MJO diagnostics were not adequate to understand why changing the ...